1. Field of the Invention
The present invention relates to molten material supply units, and may be, for example, advantageously utilized to melt materials, such as metals and/or mixtures of metal and plastic, that have relatively high melting points. The present invention also relates to molding apparatus (e.g. molding dies) that include such molten material supply units.
2. Description of the Related Art
Die-cast molds (machines) are typically used in order to mold metals into articles of manufacture. Molten metals, such as molten aluminum alloys and magnesium alloys, are usually melted in a blast furnace and then transferred to the die while being exposed to air. Thereafter, the molten metals are injected under pressure into the die. Generally speaking, die-cast molds utilize a piston-cylinder mechanism to pressurize the molten metals, so that the molten metals can be injected into the die under pressure. The injected molten metal is then cooled and solidified within the die, thereby forming a metal molded product.
However, a blast furnace is usually expensive and requires a costly installation. Further, heated gases generated when the metal is melted within the blast furnace and exposed to air may create environmental pollution. Therefore, there is a long-felt need for apparatus and methods that can inexpensively melt materials, including but not limited to metals and metal-plastic mixtures, and preferably minimize environmental pollution.